INSECTS. 101 



and flowers, and, in particular, the underground parts 

 of strawberry plants. I£, on poor sandy soil, they can 

 get nothing else, they devour the bark of oak and fir. 

 Cockchafers take three to four years for their develop- 

 ment : four in England, North Germany, and Central 

 Germany ; three in South France, Switzerland, the 

 Rhine district, and Holland. In regions where the in- 

 sect is abundant, every third or fourth year is a " chafer- 

 year," when the beetles appear in millions, while 

 scarcely a cockchafer can be found in the intervening 

 years. In districts less infested there is not the same 

 marked distinction. It therefore appears that cock- 

 chafers and their larvse are to be reckoned as injurious 

 insects : their occurrence, however, is local. Natv/ral 

 enemies: moles, shrews, bats, foxes, crow-like birds, 

 starlings, sparrows, owls, and the large species of 

 ground-beetle. Winter floods do no harm to the 

 grubs, which are then deep in the ground, — but this 

 is not the case with floods occurring in summer, when 

 they are near the surface eating the roots of the 

 plants. Remedies: Collecting the grubs turned up 

 during ploughing. Catching the cockchafers; this 

 is very expensive, since it has to be done very 

 energetically if most of them have left the pupa- 

 stage. A part of the expense may, however, be 

 recouped by using the cockchafers as manure. 



The Horse-chestnut Cockchafer {Melolontha hippo- 

 castani) has a short slender caudal process, somewhat 

 broader at the tip (Fig. 73). Its habits are in no way 

 different from those of the preceding species. 



The Buckwheat Beetle (Phyllopertha horticola), one- 

 third to one-fifth of an inch long, without a caudal 

 process. Shining blackish green, with yellowish brown 

 elytra. Dark-coloured specimens are also found. The 

 beetles appear in June ; in some years they occur, like 

 cockchafers, in large numbers. Habits of the beetle 

 and of the small grub not markedly different from those 

 of the cockchafer. 



